Four-tower rectifying method for producing biodiesel from waste grease

Abstract

The invention discloses a four-tower rectifying method for producing biodiesel from waste grease. The four-tower rectifying method comprises the following steps: (1), continuously putting reacted coarse methyl ester in a first tower to rectify so as to produce C14 and light-component fatty acid methyl ester; (2), continuously putting coarse methyl ester passing through the first tower in a second tower to rectify so as to produce C16 fatty acid methyl ester; (3), continuously putting coarse methyl ester passing through the second tower in a third tower to rectify so as to produce C18 fatty acid methyl ester; and (4), continuously putting coarse methyl ester passing through the third tower in a fourth tower to rectify so as to produce C18 fatty acid methyl ester and C20 fatty acid methyl ester. According to the four-tower rectifying method disclosed by the invention, reacted coarse methyl ester is rectified through the four towers; therefore, high-purity C16 fatty acid methyl ester and C18 fatty acid methyl ester can be obtained; and the four-tower rectifying method completely accords with production requirements of chemical products.

Description

technical field [0001] The invention relates to a four-tower rectification method for producing biodiesel from waste oil. Background technique [0002] Biodiesel is a green and environmentally friendly biomass energy. It has been used as fuel oil and petrochemical fuels in my country for more than 10 years. The quality requirements are different from those used for fuel. Since domestic biodiesel companies mostly use a single distillation technology and equipment to separate crude methyl esters, the product quality cannot meet the BD100 standard, and the marketing is affected to a certain extent. The use and chemical industry have high requirements on the purity of biodiesel (fatty acid methyl ester). The existing process only meets the pressure of using biodiesel as fuel oil, but cannot meet the purity required for the use of biodiesel as a chemical raw material. Therefore, four Column rectification technology and equipment can realize subdivision and refinement of crude me...

AI Technical Summary

Problems solved by technology

Since domestic biodiesel companies mostly use a single distillation technology and equipment to separate crude methyl esters, the product quality cannot meet the BD100 standard, and the marketing is affected to a certain extent.

The use and chemical industry have high requirements on the purity of biodiesel (fatty acid methyl ester). The existing process only meets the pressure of using biodiesel as fuel oil, but cannot meet the purity required for the use of biodiesel as a chemical raw material. Therefore, four Column rectification technology and equipment can realize subdivision and refinement of crude methyl ester, meeting the index of chemical raw materials